Returns a sort key for the character sequence designated by the iterator range [F1, F2) such that if the character sequence [G1, G2) sorts before the character sequence [H1, H2) when character case is not considered then v.transform_primary(G1, G2) < v.transform_primary(H1, H2).

Returns a sequence of characters that represents the collating element consisting of the character sequence designated by the iterator range [F1, F2). Returns an empty string if the character sequence is not a valid collating element.

For the character class name represented by the specified character sequence, return the corresponding bitmask representation.

Parameters:

begin

A forward iterator to the start of the character sequence representing the name of the character class.

end

The end of the character sequence.

icase

Specifies whether the returned bitmask should represent the case-insensitive version of the character class.

Returns:

A bitmask representing the character class.

boolisctype(char_type ch, char_class_type mask) const;

Tests a character against a character class bitmask.

Parameters:

ch

The character to test.

mask

The character class bitmask against which to test.

Requires:

mask is a bitmask returned by lookup_classname, or is several such masks bit-or'ed together.

Returns:

true if the character is a member of any of the specified character classes, false otherwise.

intvalue(char_type ch, int radix) const;

Convert a digit character into the integer it represents.

Parameters:

ch

The digit character.

radix

The radix to use for the conversion.

Requires:

radix is one of 8, 10, or 16.

Returns:

-1 if ch is not a digit character, the integer value of the character otherwise. The conversion is performed by imbueing a std::stringstream with this->getloc(); setting the radix to one of oct, hex or dec; inserting ch into the stream; and extracting an int.